Packie's father was a violent, perverted alcoholic whom Packie blames for their mob's loss of influence. He says of his father, "I used to think I loved him, but then I realised I hated him". He eventually admits to Niko that his father used to molest both him and Gerry. He developed a drug habit at fourteen years of age, and claims he was constantly staying home from school to roll joints for his dad.

Packie became involved in crime at an early age, having chosen Gerry as a role model and began spotting for his brother's scores when he was in middle school. His first conviction was in 1997 when he was arrested for stealing a car aged eighteen. The following year, he secured his first felony conviction when he was arrested for grand larceny but was (presumably) acquitted. He was arrested again in 2000 for highjacking. Packie's last known arrest was in 2005 when he was caught with several grams of cocaine in the presence of a known prostitute. At some point his father apparently committed suicide, and Gerry became the head of the McReary crime family although Packie admits that he initially suspected Gerry of killing him.

Grand Theft Auto IV

By the time of Grand Theft Auto IV, Packie largely operates independently of the Irish Mob, committing stick-up robberies with his friends Michael Keane and Gordon Sargent, and working as a hired gun for the Pegorino Family.

In the credits of The Ballad of Gay Tony, Packie is seen leaving a taxi and entering Francis International Airport carrying a duffel bag, presumably filled with money. In the following scenes, a plane is seen leaving the runway heading for an unknown destination. By 2013 he was living in Los Santos.

Grand Theft Auto V

Packie appears again in Grand Theft Auto V, appearing early in the game as he holds up a drug store in Strawberry with an un-named accomplice. Once the player finds him, he requests that they find a getaway car and help them escape. The player may do so, or assist the store owner and kill Packie and his accomplice. If they help Packie, he will thank the player and become available as a gunman in further heists. Packie has some of the highest possible skills for a gunman available, but takes 12% percent of the cut.

Interestingly, if Packie was chosen as a gunman, he mentions his biggest robbery during the drive from Sandy Shores to Paleto Bay in The Paleto Score. On the journey to the bank, the gang will talk about their first robberies. Packie mentions that one of the gunmen were killed by one of the hostages, and goes into detail regarding how they escaped. He will also mention his brother, Derrick, who was also a gunman in the Bank of Liberty robbery, and reveal that he is now dead. Lastly, he mentions Niko Bellic, the fourth gunman. Packie says that he had lost contact with Niko after leaving Liberty City, and that he doesn't even know what became of him, presuming him to be dead.

Lester Crest: "McReary? He was a part of a well known Liberty City stickup crew. Small world."

Michael De Santa: "I got a good feeling about him."

―Lester and Michael about Packie.

Packie can be selected in all the heists of the game. In The Jewel Store Job, smart or loud approach, he manages to get all the jewels in the glass cabinets, helping the crew reach the maximum possible score of the job. In the loud approach, he also stops the manager of the jewelry store before she screams for help.

In The Paleto Score, Packie survives the heist and provides good assistance against the cops. Michael even compliments Packie's help by saying that he is glad they chose him for the score.

In The Bureau Raid, he survives the explosion during the escape in the covert approach and in the roof approach, he does a good job with no consequences.

In The Big Score, subtle approach, if placed as one of the gunmen, he does not drop any gold bars while he is loading them into the Gauntlets, preventing the crew from losing any of the final score.

In the obvious approach, if he is selected as either the first or second gunman, there are no consequences to the heist. Previous experience in past heists won't change Packie's performance in any of the scores; he does a good job in all of them even if he is selected for the first time.

Personality

On the surface, Packie portrays himself as strong and without feeling. But when drunk or otherwise confiding in Niko, he is shown time and time again to be suppressing deeply painful emotions. For example, he will lament that "the world is ugly and unkind", question what being a man is all about, and contemplates suicide. He has an addictive personality, as shown by his habitual use of cocaine and prostitutes. He doesn't seem to seriously consider immediately and directly killing himself, but does glamorize the idea that he will die young of drug overdose. Compared to Niko, Packie is equally capable of violence and criminal activity whilst appearing to show little or no remorse. He does, however, still hold certain moral standards; if the player kills too many hostages during the mission Three Leaf Clover, the mission will fail and Packie will say that he doesn't take "bloody money".

Packie's cocaine addiction has caused him numerous problems. He claims that he can't look for women without cocaine in his system and when he's with women, he spends his time in the bathroom snorting rails of coke, which lowers his sex drive (he calls this a "catch 22"). Kate claims that Packie has uncontrollable behavior when he's with her in public and will attack anyone who he thinks is looking at her "wrong".

Appearance

Grand Theft Auto IV and its Episodes

Packie is slightly shorter and more slender than Niko. He also has a long scar under his left eye, possibly from fights when drunk. His nose appears to be slightly crooked, implying that it may have been broken. Patrick wears a white long-sleeved undershirt, green polo shirt, blue jeans and sneakers that look very similar to the ones in Russian Shop. He has green eyes with a grey tint, and a buzz cut hairstyle. His skin has several red spots and dents, probably due to cocaine use.

Grand Theft Auto V

Packie appears, but looks very different than in Grand Theft Auto IV. He is seen with considerably more scars, light stubble, and looks much older. The mole on the top right corner of his lip is more noticable and has developed wrinkles around his eyes. His eyes appear as a lighter auburn and are less distressed and bloodshot. His outfits are determined by his appearance in Heists. His nostrils are also more enlarged than they were five years previously in GTA IV.

Friendship

Niko and the car bomb.

At some point after completion of the mission Three Leaf Clover, Packie calls Niko to do a friend activity with him. After this event is completed, Niko will become friends with him. Packie is the fourth of five friends Niko will make within the game, and is available between 4 PM and 6 AM. He is available for six different activities; Bowling, Darts, Drinking, Pool, Show, and Strip Club.

When Packie's "Like Stat" rises above 75% (and after completing the mission "Actions Speak Louder than Words "), the player will unlock his Special Ability. Packie's Special Ability allows Niko to call Packie and ask him to prepare a car bomb, which can be used to take down difficult targets. This ability can be useful in certain situations and missions. When the player requests a bomb, Packie will inform Niko of its location. Once Niko has located the bomb, he can detonate it by calling Packie. Receiving Packie's friendship bonus will award the player the "Dial 'B' for Bomb" trophy/achievement.

3 different views of car bomb.

He likes it when Niko drives fast, saying things such as "If you have somewhere to be then you may as go at pace." and "This is the way to do it, Niko." He also enjoys fighting while on friend activities, and - as with all friends - will assist in any combat during the activity.

In Grand Theft Auto IV, Packie's favorite radio station is Liberty Rock Radio and he will respond positively if the player switches to this station whilst in a vehicle, claiming he wants it to play at his funeral. In Grand Theft Auto V, Packie's favorite radio station is Los Santos Rock Radio.

Packie dislikes playing darts, as he claims it is "boring", despite darts being a traditional Irish game and Packie being proud of his Irish roots, as he states himself. However, he only voices his disliking if the player beats him.

He will sometimes refer to Niko as "boyo", which traditionally refers to someone younger than oneself, despite Niko being a year older than Packie.

Packie is right-handed, though his artwork shows him fighting from a stance called "southpaw", which is largely used by left-handed people.

If playing as Trevor, the player can take Packie and his friend to the Altruist Cult. If taken to the Altruist Cult, Packie will mention how he used to hate going bowling and playing darts in Liberty City, but admits he misses it after spending so much time in Los Santos.

Packie, along with Gustavo Mota and Chef, is one of three gunmen that will survive throughout all the heists if hired.

If assisted in his random encounter in GTA V, Packie states that his fellow accomplice is the only person that he knows in Los Santos, however if chosen for the Jewel Store Job (his next possible appearance) he will somewhat contradict this by saying that he has met many people since moving there, speaking of their generally self-centred nature. However, he maybe just doesn't like many people in Los Santos, or has been comparing their attitudes to people from Liberty City.